1. Field of the Invention
The present invention relates to an image data processing apparatus and an image display apparatus.
2. Related Background Art
In an image display apparatus, in order to improve the quality of the displayed image, there is already known a technology of correcting an unevenness in luminance, generated for each pixel (for example, Japanese Patent Application Laid-Open Nos. 2000-122598, 2001-357394 and 2001-350442). A distribution of a luminance unevenness generated in each pixel may also vary by a gray-level to be displayed. Therefore, it is desired to appropriately correct the unevenness in luminance according a change in the gray-level. The Japanese Patent Application Laid-Open No. 2000-122598 discloses a technology of correcting the unevenness in luminance according to the change in the gray-level.
Such technology disclosed in Japanese Patent Application Laid-Open No. 2000-122598 will be explained briefly. In such technology, a table defining correction values for all the gray-levels is stored in a memory (storage means) for all the pixels, and input image data are multiplied by a correction value corresponding to such image data (more specifically a correction value (a reciprocal of a luminance when a light emission is executed with a predetermined luminance instruction value) is multiplied as a gain on a light emission instruction value) thereby causing a light emission with an appropriate gray-level. This technology allows to appropriately correct the unevenness in luminance even when the gray-level changes.
However, in the technology disclosed in Japanese Patent Application Laid-Open No. 2000-122598, it is required to store, for all the pixels, a table defining correction values for all the gray-levels in the memory. Therefore the memory requires an enlarged capacity so that the magnitude of the circuit becomes larger.
Also Japanese Patent Application Laid-Open No. 2001-357394 discloses a technology of interpolating correction data to be added to the input signal. In general, an interpolation technology can reduce the memory capacity as the data amount to be stored in the memory can be reduced.